Temperature and vapour pressure regulation device for a structure

ABSTRACT

A device in a constructional element ( 19 ), which may form a supporting element, for temperature regulation in, for example, storey partitioning elements, walls and ceilings of a building structure or refrigerating plant, in which the temperature-regulating surfaces ( 18 ) of the constructional element ( 19 ) are formed by two or more corrugated cavity-forming ( 20, 22 ) layers ( 14, 16, 18 ), the cavities ( 20, 22 ) being connected to the outlet ( 26 ) and inlet ( 30 ), respectively, of a heating/cooling unit ( 24 ) and being arranged to circulate temperature-regulated air, and in which the temperature-regulating surfaces ( 18 ) are provided with perforations ( 34 ).

This invention relates to a device for regulating the temperature andvapour pressure in a structure. More particularly, it concerns aconstructional element, which is provided with ducts for heat regulationpurposes, wherein moisture can be drawn into the ducts of theconstructional element.

In known construction and building structures the constructional elementseparating storeys is normally made of concrete, whereas walls may bemade of concrete or a plate material. The constructional elementcommonly extends between the supporting parts of the construction orbuilding structure, and is either cast on site or in the form ofready-made elements. Working with such constructional elements ofconcrete is resource demanding in separate ways. The use of a heavymaterial like concrete in the storey-partitioning element means that thedimensions of the supporting elements must be increased. Besides, eachlevel must be given an additional height of at least 30 cm in order toprovide space for ducts for the air normally used for heating and/orcooling of rooms in the construction or building structure. These areall conditions that add to the costs of known structures.

In the cooling of buildings in tropical areas, where the outdoortemperature can be in the order of 45° C. and the relative humidity canbe of up to 99%, it is evident that condensation of air humidity insidethe building can be a considerable problem The desired relative airhumidity within buildings in areas of this kind is between 40 and 60%.Condensation of humidity is also a known problem in refrigerating roomsand freezing rooms.

For the cooling of indoor air it is common to use a cooling plant of thekind in which outdoor air is cooled and blown into the building both toregulate the indoor temperature and to lower the relative humidity ofthe air. It has proved necessary to lower the air temperature at theoutlet of the cooling plant to approximately 7° C. to reducesufficiently the relative humidity of the air. This condition combinedwith the amount of cooled air that will have to be supplied to thebuilding in order to carry away the thermal energy conducted in throughwalls, floors and ceilings, entails relatively high energy consumption.

According to the prior art, in order to reduce the energy consumption tosome extent, it is common in the countries where it is permitted, to useso-called return air ventilation. That means that only part, for example20%, of the ventilation air supplied to a room is outdoor air, whereasthe remaining portion is mixed-in indoor air which only needs coolingcorresponding to the temperature increase it has had during itscirculation within the building.

It is also known to cool buildings without outdoor air being added.

The method of cooling of this kind according to the prior art is, asmentioned, relatively energy demanding, especially if an acceptableindoor air quality is to be maintained It can be mentioned that inseveral countries, including Norway, it is not permitted to use returnair ventilation It is also common that cooling plants of the kind inquestion emit considerable noise, and that the necessary air flow volumeleads to uncomfortable draught.

Norwegian patent application 19982520 discloses a device in aconstructional element included in a construction or building structure,in which a constructional element is of such configuration that itcomprises a duct system for air. The air ducts of the system runparallel to each other, the constructional element being made up of atleast three interconnected layers of corrugated place material. Thelayers are oriented in such a way relative to abutting layers that thecorrugations of two adjacent layers are perpendicular to each other. Theintermediate layer between an upper layer and a lower layer that areessentially horizontal in the position of use of the constructionalelement, is formed with a number of transversal through holes connectingthe air ducts of two adjacent air duct systems. One air duct system canserve as a supply air duct system for heated or cooled air and the otherAs an evacuating system or return air system.

However, the device according to the Norwegian patent applicationmentioned is not arranged to deal with moisture from the rooms adjacentto the constructional element.

The invention has as its object to remedy the drawbacks of the priorart.

The object is realized in accordance with the invention through thefeatures specified in the description below and in the following Claims.

A constructional element, for example to be used as a ceiling,storey-partitioning element, floor or wall is formed with air ducts in acorresponding way to that of the constructional element according to theNorwegian patent application 19982520.

The air ducts in the system extend parallel to each other, theconstructional element being made up of at least three interconnectedlayers of corrugated plate material. The layers are oriented in such away relative to abutting layers that the corrugations of two adjacentlayers are perpendicular to each other. The intermediate layer betweenthe two layers that are the external layers in the position of use ofthe constructional element is formed with a number of transversalthrough holes connecting the air ducts of two adjacent air duct system.One air duct system can serve as a supply air duct system for heated orcooled air and the other as an evacuating system or return air system.

In what follows, the external layer facing away from the room which isto be temperature-regulated is referred to as the outer layer, whereasthe external layer facing in towards the room which is to betemperature-regulated is referred to as the inner layer.

The inner layer is provided with through openings, by which humiditythat has condensed onto the layer or onto an adjacent, preferably porousmaterial can be drawn into the air duet located within.

The constructional element is suitable for use as a heat exchangerelement in buildings, for example for residential and industrialpurposes, cooling and freezing rooms or in refrigerating and freezingcounters.

Depending on the required energy transfer to/from a room, more or fewerof the constructional elements in a building can be formed in accordancewith the invention, as the constructional element has a through-flow ofair in an essentially closed circuit.

Air, which is conducted in between two abutting layers, flowsalternately along and across the corrugations of the layer, which hasthe effect that an essentially turbulent form of flow arises. Aturbulent flow has the effect that a substantial improvement of the heattransfer between gas and layer is achieved compared to laminar flow. Inprinciple, the air flowing in between layers can spread throughtransversal and longitudinal corrugations over the entire area of thelayer.

With cooled air, for example having a temperature of 17° C. flowingbetween said layers, said surfaces work as a cooling element and cankeep the indoor temperature at a desired level. The air flowing betweenthe layers can flow, for example, in a direction from a cooling unit inthe space between the intermediate layer and the outer layer, afterwhich it flows, at one or more points in the portion of theconstructional element opposite to the cooling unit, through theintermediate layer and back to the cooling unit in the space between theintermediate layer and the inner layer.

The air is then cooled to a degree corresponding to the heat quantitythat has been added to it, after which it is circulated back between thelayers. Thus, it is not necessary to cool new outdoor air in order tomaintain the cooling effect of the building elements.

Any ventilation air, which, with the use of the invention, does not haveto contribute to cooling, can ba supplied to the building in asubstantial smaller amount compared to the prior art. Normally it willnot be necessary to cool this flow of air.

As the side of the corrugated inner layer of the constructional elementwhich is placed on the side of the constructional element facing theroom is perforated, the excess humidity which is supplied to thebuilding, for example together with the ventilation air and settles onthe relatively cold inner layer, will be drawn into the cavity betweenthe perforated inner layer and the intermediate layer. The humidity thenfollows the cooling air to the cooling unit where it condenses and iscarried away.

In what follows is described a non-limiting example of a preferredembodiment which is visualized in the accompanying drawings, in which:

FIG. 1 shows schematically a sectional plan view II-II of FIG. 2 of abuilding, in which the ceiling, floor and walls are provided withcorrugated plates according to the invention;

FIG. 2 shows schematically a section I-I of the building of 20 FIG. 1;

FIG. 3 shows a perspective section of the floor of FIG. 2, in whichthree corrugated layers lying on top of each other are placed in acovering way over the foundation. The slab of the floor is not shown;and

FIG. 4 shows, in a section, an alternative embodiment, in which theconstructional element is used as a storey-partitioning element in abuilding, and in which the walls are also formed by constructionalelements according to the invention.

In the drawings the reference numeral 1 identifies a building comprisingwalls 2, 4, 6, 8, a floor 10 and a ceiling 12. Other necessarystructural details like doors and windows are not shown

The floor 10 and the ceiling 12 are provided with three coveringcorrugated layers, one above the other, in the form of plates 14, 16 and18, and 14′, 16′ and 18′, respectively, in which the corrugations of theintermediate plate 16, 16′ lie at an approximately right angle relativeto the corrugations of the outer plate 14, 14′ and the inner plate 18,18′. The plates 14, 16 and 18, and 14′, 16′ and 18′, respectively, areconnected to each other and to the floor 10 and ceiling 12 by means of,for example, glue, screws, dowels or by means of other securing meansknown in themselves. The interconnected plates 14, 16 and 18 form aconstructional element 19 which may be load-bearing. The walls of thebuilding are also provided with a constructional element 19.

A cavity 20, see FIG. 3, located between the outer plate 14 and theintermediate plate 16, and a cavity 22 located 20 between theintermediate plate 16 and the inner plate 18, are sealingly defined bythe walls 2, 4, 6, 8 and basically form a closed cavity each.

A cooling unit 24 of a kind known per se is placed on the wall 2 and isarranged to circulate cooled air in the floor 10. The outlet side of thecooling unit 74 is connected to the cavity 20 located between the outercorrugated plate 14 and the intermediate corrugated plate 16 by means ofan admission duct 26. Cooled air flows in the cavity 20 like the arrow Ashows, see FIG. 3, to at least one through opening 28 of theintermediate plate 16 near the wall 6. From the openings 28 the airflows like the arrow B shows, through the cavity 22 back to the coolingunit 24 by a return duct 30. The cooling unit 24, the corrugated plates14, 16 and 18 of the floor 10, the openings 38 and the ducts 26 and 30thus form an in principle closed cooling circuit which is arranged tokeep the floor temperature at a desired level

Correspondingly, the corrugated plates 14′, 16′ and 18′ of the ceiling12, together with the cooling unit 24′ and necessary ducts and openings,form an in principle closed cooling circuit in the ceiling.

Ventilation air is supplied to the building via a blower 32 Excesshumidity in the supplied ventilation air will condense onto the coldestsurface in the building, being the inner 20 plates 18, 18′ by the use ofthe invention. By providing the inner corrugated plate 18, 18′ withperforations 34, the condensed humidity can be drawn into the space 22and follow the cooling air to the cooling units 24, 24′ where thehumidity condenses and is drained away. The inner corrugated plate 18can possibly be replaced by a porous plate, not shown. A volume of aircorresponding to the volume of ventilation air flowing in through theperforations 34 flows out into the surrounding from the cooling units24, 24′.

In an alternative embodiment, see FIG. 4, constructional elements 19 aredimensioned for, and used as, respectively, the supporting partitioningfloors 36 and walls 38, and floor 10,

By the use of the method according to the invention a substantialimprovement of the indoor climate is achieved compared to the prior art,while at the same time the reduction in the amount of air that needs tobe cooled entails a considerable reduction in the use of energy.

The use of the constructional element 19 in cooling and freezing plants,not shown, will have the effect that there will be an improvedenvironment in the plant.

1. A device in a constructional element (19) which may form a supportingelement, for temperature regulation in, for example, storey partitioningelements, walls and ceilings of a building structure or a refrigeratingplant, in which the temperature-regulating surfaces (18) of theconstructional element (19) are formed by two or more corrugatedcavity-forming (20, 22) layers (14, 16, 18), the cavities (20, 22) beingconnected to the outlet (26) and inlet (30), respectively, of aheating/cooling unit (24) and being arranged to circulatetemperature-regulated air, characterized in that thetemperature-regulating surfaces (18) are provided with perforations(34).
 2. A device in accordance with claim 1, characterized in that inthe portion of the intermediate corrugated layer (16) preferably locatedthe farthest from the outlet (26) and inlet (30) of the heating/coolingunit (24) there is arranged at least one connection (28) between the twosides of the plate (16).
 3. A device in accordance with claim 1,characterized in that the inner plate (18) is formed by a porousconstructional element.
 4. A device in accordance with claim 2,characterized in that the inner plate (18) is formed by a porousconstructional element.